G Force (two halves sticking together

I have read a couple of threads here on TRF that warn that the two pieces of the G force should be sanded until they separate with relative ease. I have been sanding the heck out of the two pieces and still the are very tight. Any special tips or do I continue to sand them?

I guess you want to sand until they fit good. Finish sanding with 400 or 600 grit to get nice and smooth. I also "cut"/ round the inside edge of the upper body tube and the outside edge of the coupler.

Check the inside edge of the tube if you haven't already done so. There is often times a "lip" there from the cutting process. Coating the surfaces with thin CA makes obtaining a clean finish and good fit much easier also.

Peel off a layer of paper to give a looser fit. Sanding takes too long and often leaves it still too tight. The fit can also change with temperature.

Thank you for the info. I will use these ideas. I just want to make sure that my G Force doesn't end up a lawn dart on her maiden voyage.

She's a looker! Nice job.

Electronhammer said:

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Oh damn! That's a sexy rocket!

WOW!! :surprised: Great look,,,Airbrush????

Thanks. That's the main reason I don't want her to lawn dart. I mean, I don't want any rocket to lawn dart, but I especially don't want her to return to Earth in that manner. I did spend some time on her finish. I used an airbrush and finished her with Future Shine and polished her out with Meguiar's Gold Class automotive polish.

I'm still trying to get the hand of my airbrush. I can only hope that someday my work will look as good as yours.
With my GForce it "asphaltdarted" and the cause was determined to be either not enough BP in the ejection charge, the "cooling mesh" or a combo both.
I have since rebuilt it and flew it with no problem.
I eliminated the cooling mesh and replaced the shockcord with a Kevlar/Tubular nylon combo and wrapped the chute in a Kevlar blanket. I also replaced the coupler with a LOC coupler and used the stock one to beef up the aft section on the lower BT. It slides nicely now. I have read that others have had the same problem you are with the coupler so maybe they have a bad batch of them in the the latest kits.

race 58 said:

I'm still trying to get the hand of my airbrush. I can only hope that someday my work will look as good as yours.

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Thanks. Actually, I am still working on my airbrush technique. If, you were to look close at the rocket in person, you would be able to see a couple of places where I messed up. I am still practicing with cardboard from pop and beer cases and anything else I can get my hands on. My garage is filled with many very colorful pieces of cardboard and scrap wood.

race 58 said:

I eliminated the cooling mesh and replaced the shockcord with a Kevlar/Tubular nylon combo and wrapped the chute in a Kevlar blanket.

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This Kevlar blanket is attached to the shock cord along with the chute?

Yeah--there's Kevlar blankets (I think Giant Leap sells them?) used sometimes instead of the Nomex. And like the Nomex, they have means to attach to the shock cord so they can be re-used.


Later!

--Coop

Electronhammer said:

I have read a couple of threads here on TRF that warn that the two pieces of the G force should be sanded until they separate with relative ease. I have been sanding the heck out of the two pieces and still the are very tight. Any special tips or do I continue to sand them?

Click to expand...

E-hammer-fwiw, I burnish in some powdered graphite from Wally World or similar (it's where they sell keys or sporting good ususally) on each face of the joint by dropping some on and rubbing it in with my finger and it's never failed me. I have a couple of G-Forces I had to do that to, also. It helps to apply some thin CA so they remain stiff and then sand them out till smooth (before the graphite treatment. Excellent flyer. BTW-Very nice looking bird!

Thanks fyrwrxz. I'll work on her some more tonight.

Electronhammer said:

This Kevlar blanket is attached to the shock cord along with the chute?

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Coop is corrrect about Giant Leap that's where I got mine, but I'm sure others sell them as well.
https://giantleaprocketry.com/products/components_recovery.aspx#Parachute_Protectors

The shockcord goes thru a hole in the Kelvar blanket and you can then slide the blanket up and down the cord.

Here is a video I made about they way I set up the recovery system.
https://www.youtube.com/watch?v=4pN6XSHBJtE
Others may have different methods but this is what works for me

Hope this helps.
Ed

Is the G-Force designed as a "MID" separation rocket? I just thought the nose cone blew off at ejection?

Std breaks in the middle. I guess you normally just glue the nose cone on. Waste of payload area.

It seems as if the last batch of G-Force kits have had overly large couplers. Some people have suggested it's because of the lack of humidity where they are made (AZ?) versus where you are. It seems to me like they are being manufactured at the wrong size. I mean if you have to pull more than a layer or two of material from a kit, then something is wrong with that part. You may want to replace it with a thicker coupler that will fit the ID.

My GForce was not even close to fitting and took a great deal of sanding to fit and still lawn darted (blew the bulkhead off the coupler). I was worried about making the coupler too thin so I probably didn't take off enough material.

fyrwrxz said:

Std breaks in the middle. I guess you normally just glue the nose cone on. Waste of payload area.

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I used rivets to hold the nosecone on so I can use the space when needed.
I also used them on the coupler and lower BT for the same reason.

AfterBurners said:

Is the G-Force designed as a "MID" separation rocket?

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Yes

fyrwrxz said:

E-hammer-fwiw, I burnish in some powdered graphite from Wally World or similar (it's where they sell keys or sporting good ususally) on each face of the joint by dropping some on and rubbing it in with my finger and it's never failed me. I have a couple of G-Forces I had to do that to, also. It helps to apply some thin CA so they remain stiff and then sand them out till smooth (before the graphite treatment. Excellent flyer. BTW-Very nice looking bird!

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Speaking of G-Force, what brand or where did you get your coooool tail cone for your GForce BLACKOUT ? It really makes it stand out !

Kenny

r12ski said:

I was worried about making the coupler too thin so I probably didn't take off enough material.

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I have the same concern. That is why I didn't want to start pulling layers of materials away.

I was worried about making the coupler too thin so I probably didn't take off enough material.

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You can always reinforce it from the inside with scrap cardboard (wrapping paper tubes or the like) and end up something stronger then it started out.

I also noticed my tube coupler is the same way...BTW - Dave the new fins came do you still want the old ones?? I'll probably pick up a couple LOC/or Giant Leap couplers for my G.. probably start building it next month...got a couple rockets to paint first.

Just go ahead and replace the coupler with a better one from Giant Leap,, hell it's only $4.49 here:
https://giantleaprocketry.com/products/components_airframes.aspx#Coupler_Tubes

race 58 said:

Just go ahead and replace the coupler with a better one from Giant Leap,, hell it's only $4.49 here:
https://giantleaprocketry.com/products/components_airframes.aspx#Coupler_Tubes

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I will probably do that sometime. Thanks

How big of a Kevlar shock cord should I use on my G Force, diameter and length? Flat or round?

Electronhammer said:

I have the same concern. That is why I didn't want to start pulling layers of materials away.

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You should never have to do this to any kit if it was design right to begin with

Electronhammer said:

How big of a Kevlar shock cord should I use on my G Force, diameter and length? Flat or round?

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The video in post #16 above will show you what I used and how I hooked it up.